My betta has had problems with fin rot in the past,but this doesn't seem like fin rot he had a bump on his dorsal fin that was discolored a whitish bump,and now the bump is gone ,but halk of his dorsal fin is off and the rest of his win looks like it is hanging by only a little bit of skin I know for shore that this top fin will come off soo hes sitting on the bottom of the tank now. I did put some aquarium salt in the water. No I dont have a camera and I dont have another tank to put him into so what can I do will his dorsal fin grow back. I do notice new growth on his tail fins ,but I'm worried about his dorsal fin.

Housing
What size is your tank? 10 gallon
What temperature is your tank? 78F
Does your tank have a filter?yes
Does your tank have an air stone or other type of aeration?no
Is your tank heated?yes
What tank mates does your betta fish live with? 4 zebra danios 5 neon tetras 2 cory cats 2 snails

Food
What type of food do you feed your betta fish?betta min and tropical flakes
How often do you feed your betta fish? Twice a day
Maintenance
How often do you perform a water change?evey weeek maybe every 2 weeks
What percentage of the water do you change when you perform a water change? 40 %
What type of additives do you add to the water when you perform a water change? Algy control,Plant vitamens Water conditioner Aquarium salt

Water Parameters:
Have you tested your water? If so, what are the following parameters?

NOSymptoms and Treatment
How has your betta fish's appearance changed?Fins became ragedy
How has your betta fish's behavior changed? still active
When did you start noticing the symptoms? 1 month ago
Have you started treating your fish? If so, how? Aqurium salt more water changes
Does your fish have any history of being ill? Fin rott
How old is your fish (approximately)? I got him Last January so maybe a year old?

Ayour tank is overstocked. The danios should be in a larger tank, and the corys need to be in a group of 3-4. you aren't doing enough water changes, and aquarium salt isn't a water conditioner/dechlorinater. You really shouldn't use aquarium salt for more than ten days of treatment, because continued exposure can cause organ failure in fresh water fish.

ragged fins is a sign of fin rot, due to bad water quality. In a tank that stocked, you'd need to be doing larger 60% or more water changes at least once a week, probably more.

You should test or get your water tested. I'm willing to bet ammonia, nitrites and nitrates will be through the roof.

oh, raggedy fins might be tailbiting due to stress, but it's probably finrot.